On a conventional production line for products, such as foodstuffs, an X-ray inspection apparatus is used to inspect for defective products in order to prevent the shipment of such products, such as those that are cracked or contaminated with foreign matter. With this X-ray inspection apparatus, products to be inspected are irradiated with X-rays while being continuously transported by a transport conveyor. The transmittance state of those X-rays is detected by an X-ray receiving unit, and a determination is made as to whether each inspected product is contaminated with foreign matter, whether it has cracks, whether there is a shortage in the number of items it contains, and the like. In addition, there are also cases in which the X-ray inspection apparatus performs an inspection that counts the number of the items in the product to be inspected.
In such an X-ray inspection apparatus, if the inspection target is a product like a foodstuff, then the transport conveyor is repeatedly dismounted and cleaned in order to maintain sanitary conditions. If the transport conveyor, which is repeatedly mounted and dismounted any number of times, is not mounted at the normal position when remounted, then there is a risk that the X-rays will scatter inside the apparatus and leak to the outside of the apparatus if the X-rays are irradiated with the transport conveyor in this state.
Consequently, an X-ray inspection apparatus has been proposed (refer to Patent Document 1) that is provided with a function for verifying whether the transport conveyor, which transports the products to be inspected, is properly mounted. With the X-ray inspection apparatus disclosed in Japanese Published Unexamined Patent Application No. 2002-71588 (published on Mar. 8, 2002), an open state detecting device is disposed at the mount position of the transport conveyor inside the apparatus, and if the transport conveyor is not properly mounted, then the open state detecting device detects the unshielded state and prohibits the irradiation of X-rays. Thereby, the leakage of X-rays to the outside of the apparatus is prevented when the X-rays are irradiated in the state wherein the transport conveyor is not properly mounted, as well as in the state wherein the mounting of the transport conveyor has been neglected.